Cherry-pick 263009@main (1c9024b). https://bugs.webkit.org/show_bug.c…

…gi?id=255491

    [GTK] Error if gettext is not found during configure
    https://bugs.webkit.org/show_bug.cgi?id=255491

    Reviewed by Michael Catanzaro.

    Previously it would fail later during build.

    * Source/WebCore/platform/gtk/po/CMakeLists.txt:

    Canonical link: https://commits.webkit.org/263009@main

Source/WebCore/platform/gtk/po/CMakeLists.txt

@@ -1,5 +1,9 @@
 include(FindGettext)
 
+if (NOT GETTEXT_FOUND)
+    message(FATAL_ERROR "gettext not found")
+endif ()
+
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